Heat recovery method and means



M. WA STOUT July 2s, 1936.

HEAT RECOVERY METHOD AND MEANS Filed March 6, 1933 3 Sheets-Sheet 1fille' IIII'II IlIII.

NIN i INVENTOR.

J1 ly 28, 1936. M. w. sToUT HEAT RECOVERY METHOD AND MEANS 3Sheets-Sheet 2 INVENTOR.

Filed March 6, 1933 July 28, 1936. M. W STOUT 2,048,759

HEAT RECOVERY METHOD AND MEANS Filed March 6, 1933 3 Sheets-Sheet 3INVEN TOR.

Patented July 28, 1936 mais ` 2,048,759 HEAT \RECOVERY METHOD ANDMEANS AMinor W. Stout, Kansas City, Mo.

Application March 6, 1933, Serial No. 659,729 12 Claims. (ci.1.22".-396) This invention relates to improvements in heat recoverymethods and means, and more particularly to a system for the recovery ofthe heat content of steam and water from steam boilers,

such that, following cleaning or inspection `of the boiler, asubstantial part of the original heat content may be restored to a freshsupply of boiler feed water. The system to be described by Way ofexemplifying the invention, illustrates a preferred and improvedpractice in the recovery of heat from locomotive boiler blowoff iiuids.

As conducing to a better understanding of the advantages of the methodand apparatus identi-V fied with the present system, it may be notedthat the heretofore prevailing practice of washing and cleaninglocomotives upon arrival thereof in a roundhouse after a run, consists,first, in blowing 01T the boiler water, containing a substantial amountof mineral; this water existing at a temperature of the order of 360 F.,corresponding say, to pounds gauge pressure. The blowoff operationusually takes place by connection of the locomotive boiler, say to ablowoif header, and thence into a blowoff tank. At usual temperature andpressure a great deal of ash steam is usually given off, connectionbeing made from the blowo header, according to prevailing practice, to anozzle in the feed water storage tank, so that the resulting flash steamis utilized in some measure, to heat the boiler feed Water which may besupplied from a suitable softener or from the mains. After completion ofthe blowoff operation, the water taken from the blowoff storage tank iscooled down with fresh Water, say to a temperature of 120-130 degrees F.This Water is forced as by a steam driven pump, at about 100 poundspressure, into the mud drum of the locomotive. After the mud and scaleis there loosened up and removed, the washout water is run to thesewers. Water from a clean Water storage tank is then delivered to theclean locomotive boiler, at say 180 degrees temperature. The locomotiveis then again ready to be red, and

after some little period of time is enabled again change of conditionsthat, at the start of the resteaming operation, the same locomotive willcontain say 3,500 gallons of fresh feed water at a temperature of nottov exceed 180 degrees. The foregoing operation, while subject of courseto the varying practices of different railroads, serves to typify theheat' Waste normally incident to the practice prevailing before theadvent of the present system.

An object of the invention may thus be generally stated as theimprovement of facilities for reclaiming heat from blowoff boiler uids,resulting in a greater recovery of the heat content of boiler drainageand flash steam, than is possible through the use of the prevailingfacilities for this purpose.

Another object of the invention is attained in an improved combinationof blow-olf storage tanks and interconnecting lines, with heat recoverydevices adapted respectively for the transfer' of heat. from the blowoifwater to the boiler feed water, and for the transfer of the heat unitsof blowoif steam, to a fresh Water supply utilized for refilling theboiler, for example, after cleaning or inspection.. Y

Still further objects are attained in an interconnected or functionallyrelated aggroupment of apparatus, suchl that asubstantial part of theboiler'blowoi water and steam may be temporarily stored under asubstantial pressure; in the utilization of improved heat exchangingfacilities, such that` a portion of the blow-olf Water and/or steam maybe conducted in heat transferring relation to a supply of fresh make-upwater; further in a combination of apparatus such that all or a portionof the flash steam from the blowoi uid is caused to deliver asubstantial'part of its heat content for preheating a supply of cleanboiler feed Water.

Numerous other objects are attained in substantial improvements in theindividual items of equipmentutilized in the combination or system;among these may be mentioned an improved reservoir for receiving theincoming liquid in a heat exchanger of counterflow or zigzag type; animproved arrangement forv circulating liquid within the tubes of such aheat exchanger; an improved strainer for use in connection with thepumps, or some thereof, of the present system. It is t0 be noted,however, that certain of the embodiments of these objects are perhapsapplicable to apparatus other than the units of the present system. y

The foregoing and many additional objects will appear from the followingdetailed description of the items of apparatus going to make up thesystem, and the technique involved in their use, considered inconnection with the accompanying drawings, in which:

Fig. 1 is an elevation illustrating in part diagrammatically, thedifferent items of apparatus employed in an existing system, accordingto the present invention, certain items of the apparatus beingillustrated in vertical sectional elevation to disclose parts internallythereof; Fig. 2 is a side elevation of a heat exchanger of a typepreferably employed in connection with the system of the presentinvention; Fig. 3 is a vertical section along line 3-3 of Fig. 2; Fig.-4 is a horizontal section along line 4 4 of Fig. 1, being taken througha heater head or steam water heating device, as utilized according tothe present invention; Fig. 5 is a section along line 5-5 of Fig. 1;Fig. 6 is a longitudinal sectional elevation of a steam ejector deviceemployed in the present system; Fig. 7 is a plan view, and Fig. 8 is aside elevation, of a preferred form of strainer such as utilized inconnection with the pump intake of portions of the system.

The invention is `herein described with reference to an installation ofheat-recovery and transfer means, in a railroad roundhouse, as thereutilized for reclaiming heat from the drainage and blowing-off oflocomotive boilers. My preference is to provide, say along the wall ofthe roundhouse, a plurality of headers whereby the heat recovery plantmay be installed in such location as not to interfere with the trackageand other usual roundhouse equipment and floor space. There isaccordingly provided a blowoff header I 0, a washout header I2, and aWater header I4, for boiler fillup water. Each of these headers is inthe nature of a manifold, which may be dead-ended at its termini. Eachof the headers is provided with a suitable flexible connection (notshown) adjacent each of the locomotive stall tracks of the roundhouse.This arrangement permits a fluid connection or a plurality thereof to bemade from any locomotive on any of the roundhouse tracks, into any orall of the headers, as may be desired.

The blowoif header or pipe I0 is directly connected, as by a pipe lineI6, through a valve I8, to an accumulator tank 20 of substantial size,and pressure resistant; a valved branch pipe 22 also serving to connectthe line I6, through a valve 24, to a blowoff water storage tank 26.

The tank 26 is provided internally with a discharge line '28, having itsinlet 30 submerged, but kept near the upper surface of the liquid withinthe tank as by a float 32. The sections of pipe constituting the line 28are jointedly connected, as through flexible or swing joints 34, adetail of a joint suitable for this purpose being shown in section inFig. 5.

The line 28 in passing out of tank 26, serves to direct the flow ofwater into the uppermost pass of a heat exchanger, indicated generallyat 36. The details of an exchanger of a suitable type are set forth inmy copending application of Serial No. 561,132, filed September 4, 1931,wherein the exchanger is described and claimed. It is thought sufficientfor purposes of present description to note that the exchanger 36comprises a series of convergently and divergently directed troughelements 38, which, however, may be closed completely so as toconstitute pipes rather than troughs. The elements 38 thus arranged inzigzag manner, are closed at their ends by headers 40, extending betweenand interconnecting which are a plurality of tubes 42 (see Fig. 3). Eachof the trough elements is provided with a discharge opening at itslowermost e`nd so that the tubes and headers on the one hand, and theconduits or troughs 38 exteriorly thereof, on the other hand, constitutetwo complete contiguous circulatory systems operating as a liquid heatexchanging device of countercurrent type. In the system presentlyillustrated the uppermost element 38 is supplied from the discharge endof the pipe 28, the flow therefrom being crosswise of and from top tobottom of the exchanger. The system of tubes 42 and headers 40 isconnected into a fresh water line 44, preferably supplied from awater-softening device of any usual form.

As will appear from Fig. 2, it is my preference to provide the exchanger36 with a water box |00, shown as disposed at the upper end of theexchanger, and in the inlet portion of the system of troughs 38. Thewater box |00 may consist of a structure of rectangular transversesection, formed of sheet metal provided with side elements of taperingheight, and supported at one end as shown, by a bracket lill, andconnected for support at the opposite end to the uppermost header 40.The inlet pipe 28 is preferably directed into one or the high end of thewater box |00. The box is provided with a baiile element extendingtransversely thereof and indicated at |02, the baille being disposed atan angle say of 30 degrees to the horizontal. The baie and box serve toreduce the velocity of flow from the pipe 28 and thus tend to promotesettling or precipitation of any solids suspended in the inflowing wateror other liquid. The box |00 is provided with an outlet or dischargeopening I03 closely overlying the upper end of the uppermost trough 38of the exchanger.

A further improvement in the exchanger'36, over the form in which it isdescribed in my copending application, Serial No. 561,132, abovereferred to, consists in the addition, within each, or at least certain,of the tube elements of the exchanger, of a spiral thimble structureindicated generally at |04. The location and form of the spiral thimblesbest appears in Fig. 2, each thimble consisting of a strip of metal,originally at in form and of suitable gauge, preferably of anon-corrosive material. Each thimble |04 is formed by twisting such astrip so as to produce thereof a spiral element, the outside dimensionsof which correspond substantially to the inside diameter of the tube inwhich the thimble is disposed. At one, say the uppermost end of the tubein which the thimble is disposed, is provided an L shaped extension |05,the length of this extension so exceeding the diameter of the tubecontaining the thimble, that the thimble is positioned againstdisplacement resulting from ilow of liquid through the tube. The thimbleserves to produce a rotary motion of the uid as it proceedsv through thetube, and serves definitely to prevent stratification of the liquidwithin the tubes. By thus subjecting the liquid content of the tubes toa slow rotary, or perhaps a whirling motion, depending upon velocity, agiven length of tubing will serve with greatly increased efliciency as aheat transferring agency.

A convenient mode of installation is to locate the heat exchanger 36above a washout water storage tank 46. The tank 46 is providedinternally with a standpipe or overflow pipe 48, which is by preferencereadily removable from the tank 46 for purposes of cleaning; The inletto pipe 49 is kept appreciably above the bottom of the tank, so that thelowermost portion of. the tank may provide a trap or reservoir for scaleand foreign matter which may precipitate in the tank 46, the capacity ofwhich is such as to require removal of accumulated solids only at wideintervals.

Connected into the upper portion of tank 46, is arr intake pipe 58directed to a pump 52 discharging into a pipe line 54 directed into thewashout header I2. The pump 52 may be of any suitable type, but mypreference is to utilize a centrifugal or. other revolving impeller typepump at this point in the system, steam pumps of usual reciprocatingtype having been found inferior thereto in actual practice. The tank 46is conveniently disposed as shown by Fig. l, partly below the groundline or floor level, and with the standpipe or overflow i8 somewhatabove the intake to pump 52, obviating any difficulty of maintaining thepump 52 in prime.

As a storage reservoir for fresh boiler llup water, there is provided atank 56, disposed above and communicating with which is a water heaterhead of steam-contact type, the head being indicated generally at 58(Fig. 1) and shown in detail in Fig. 4. The construction and arrangementof parts in this device are fully described in Letters Patent No.1,879,582, issued to this applicant under date of September 27, 1932.Briefly described, this device consists of a casing 66 of open end,flattened cylindrical form, provided with tangentially arranged, opposedsteam inlet openings 62. Branch pipes 64 serve, together with a steamline 66, to direct flash steam from the blowoff storage tank 26, topoints peripherally and internally of the casing 66. Disposed centrallyof the casing 66 is a cluster fitting 68, providing two separate sets ofwater inlet nozzles 'I0 and 12. A connection T4 is provided from theupper set of nozzles l2, to the header I4, for a purpose hereinafterappearing. The lower set of nozzles 'lil is supplied from a water line16, directed from the uppermost header 40, and hence from the inner ortube circuit of the heat exchanger. The arrangement of the heater headis such that, as a water supply from either or both of the pipe lines'I6 and I4 is sprayed upwardly through the steam zone it hits the top ofcasing 6D and falls back through the same steam zone and out the bottomof casing 66 into fresh llup tank 56. Flash steam entering through thetangential openings 62 gives up its heat content or a substantial partthereof, to the incoming water, which immediately descends by gravity,through the lower open end of the heater head 58, and thus into thefresh feed water storage tank 56. Water to be utilized for boilerrefilling purposes is withdrawn from the tank 56 as through a jointedline 'i8 provided with flexible joints 34 which may be similar to theswing joints in the line 28. As in the blowoff water storage tank 26,the inlet to line 'I8 is kept submerged, and spaced slightly from thetop of the water level in tank 56, as by a float 8B, to secure thehottest and cleanest water available. The line 'I8 is directed outwardlythrough the wall of tank 56, thence to the inlet of a centrifugal pump,or other suitable displacement means, indicated at 82. The outlet frompump 82 is connected as by a line 84, through a steam ejector 86, thenceinto the feed water header I4. The fitting 86 consists of an ejectornozzle, provided preferably with a T- shaped body, the lateral branch ofwhich is connected as through a valve 88 into the upper portion of theaccumulator tankv 20, for a purpose more fully hereinafter appearing. Acheck valve 89' is also desirably disposedbetween the accumulator 28 andthe valve 88.

The details of structure and the. internal arrangement of parts of apresentlyr preferred formv of ejector such as 86, best appear in Fig.6,v wherein the fresh water pipe 84 is shownas con-r to permit theentrance of steam from the'cham- I ber within the body, steam beingsupplied: there-l to through the pipe, |08 from the accumulator.. Anauxiliary fitting H3 forms a prolongation of the Venturi element I I2,the members I I2 and H3. being telescopically connected and detachablycarried by the body as by threaded cap screws. H4. At the outer end ofthe extension II3 is.v connected a pipe H5, directed into the header I4above described.

In operation,` as theA fresh water is introduced under pressure to thesleeve |09, the augmented velocity due to the throat portion of theVenturi elements, creates a suction within the inlet end of the Venturifitting I I2 which is open to receive the steam from theY accumulator20. The steam-v receiving portions of the structure are thus subjectedto a somewhat reduced pressure or suction, with the eifect that thefresh. water becomesE mixed with the flash steam from the accumulator2G, and serves to heat the fresh Water before introduction thereof tothe header I4. The type of steam ejector here described, is available tothe trade for numerous other uses, and does not, of itself, constitute apart of the present invention. Hence, no claim is made tothe deviceexcept in combination with other items of ap-Y paratus herein described.

It will be understood that. other valves may be. interposed intheseveral headers, water lines and. steam lines, at desired locations; itis mypreference, for example, to locate a valve 9U in a. j

a considerable amount of foreign matter or sludge .i

in suspension, it is my preference tol provide thev inlet to the pump 52with a strainer or the like,

which will prevent the entrancev of solids to` the y pump and to theline into the header I2. For'. this purpose I have devised a strainershown in. preferred form in Figs. 7 and 8. This structure. may besupported within the tank 46 as by asuitable bracket I20 carried by awall of the tank. TheV strainer properv consists of a base plate I2 Iwhich may be bolted or otherwiseafilxed to the bracket |26. The plateI2I is provided with recesses, say of circular sectiorn'to receive: inspaced relation a plurality of vertically dis.- posed pins or rods I22.These. rodsl are,4 in thel example shown, arranged in the form oi?` asquare,` with the rods so spaced as to restrict the size ofi solidparticles which may pass therebetween. The relation of the externaldiameter of pins I 22 and the recesses therefor in the base plate I2I issuch that the pins may be driven into the rel their entire exposedlength.

' The intake fitting for the pump 52 is shown at |24 as consisting of anelbow turned soas to present its opening' parallel to the plate |2I, and.spaced thereabove. The elbow is carried by the intake pipe' |25connected to the pump 52.

` fAn advantage of the present structure is found inthe ease of cleaningthe strainer of accumulated solids. It will appear that the water hasaccess to the intakerfrom all sides of the pinscreen structure, andhence any entrained or occl-uded solids will be trapped against theext'erior surfaces 'of the pins.` After a period of use, or when theaccumulation of solids necessitates their removal, an ordinary gardenrake may be employed, andthe foreign material .removedfrom along thepins either by direct lateral disengagement of the material, vor byraking. it upward along the pins and away from the tops thereof. Thelatter practice has been found particularly advantageous where theentrained or filtered material consists of fibrous or like substances,it being understood that. the described pin-type strainer may beadvantageously utilized at other points in the present system, or inconnection with pumps or pipe lines handling a great variety ofsolid-containing liquids, and emplcyed with other apparatus.

It will be.v understood that the foregoing description2 of partsintentionally komits certain details of structure of lesser importanceand which lwill suggest themselves to'those skilled inth'e'art.- Forexample, such of the piping as desired, and certain itemsV of equipmentemployedfo-rstorage or heat exchanging purposes, may be heat insulated.Sludge drains (not shown) may also be provided in the tanks 20, 26, and56.A Obviously also the space relation prevailing between the differentitems of apparatus as depicted in Fig. 1, is not necessarily adhered toin practice. The arrangement of parts may obviously be employed inl`accordance, with the space conditions prevailing in a particularroundhouse, or a stationary boiler installation.

According to the practice of the present invention, when a locomotive isbrought into the roundhouse, containing, say 3000 gallons of waterat'say 360 F., or 150 pounds steam pressure, the locomotive is connectedinto the blow out header l0, valves24 and 88 are closed, and valve I8opened, so that a part of the-blowoff water and s'teamare `dischargedintovthe accumulator 28. The accumulator is so'proportioned that it willaccommodate enough concentrate to secure a favorable heat balance, at apressure say of 40 pounds. The remainder of the boiler water with itscorresponding heat content, at this time remains inthe locomotive. Valve|8 is no-w closed so that the necessary heat is held in the accumulator28, at a gauge pressure, say'of 40 pounds, corresponding to 287 F. Valve24 is then opened, so as to connect the header ID, through line,22,-with the blowoff water storage tank 26,

4and the remainder Yof the locomotive sludge water at say 40 poundspressure, is conducted into the'tank 26. The substantial amount of flashsteam which results from the entrance of the blowoff water into tank 26,is conducted through line 66 and thence into the tangential steamopenings 62 of the heater head 58. During this time fresh water, say at4080 F., proceeding fromthe softener or other supply, is being.conducted through the line 44, thence through the tube and headersystem of the ex-v changer 36, thence outwardly through the pipe line'l5 to one or other lower set of the nozzles, such as 18, of the heaterhead 58. It will appear that the water in line 16, prior to its entranceto the heater head, will have been heated substantially by conduction inthe exchanger, due to the countercurrent flow of hot water from the tank26.

Water from the` nozzles I8 and/or 12 of the heater head, is brought intocontact with the whirling jets of flash steam, which augment the heatcontent of the fresh water supply, the steam-treated water beingdelivered by gravity into the fresh-water tank 55, at a temperatureofthe order of 140-180 degrees F.

As the blowoif water from tank 26 is conducted through the line 28, andthence into the heat exchanger 36, preferably the outer elements orcircuit thereof, the blowoff water is cooled to a temperature of 130degrees F. or lower, this cooling operation, aswill have been observed,serving to heat up the incoming fresh water in conduits 44, 48, and 42,enroute to the heater head. This cooled blowoil' water may be deliveredby gravity from the exchanger 36, directly into the washout waterstorage tank 46 where it is available through pump 56, line 54 and thewashout header 2, for purposes of cleaning the locomotive, interiorly`and exteriorly. At this temperature the water may be safely handledthrough a hose or other exible conduit for washing purposes. As willhave appeared from the description of structure, the overow pipe 48 fromthe washout. storage tank 46, serves automatically to remove Aanyblowoff water in excess of actual requirements for washing purposes. v

Since a substantial cooling of the blowolfwashing water occurs in theexchanger, a substantial precipitation of mineral content will takeplace in theV tank 46, which thus serves as a settling basin. Thelocation of pipes 48 and 50 above the bottom of the tank, permits aperiodic removal of sludge or precipitate, and entraps these solidmaterials, preventing any further circulation thereof through thesystem.

vAfter thorough cleaning of the locomotive by means of the wash waterfrom the tank 46, fresh feed water for refilling the boiler is pumpedfrom the storage tank through line '|8, pump 82 and line 84 into thefeed water header I4, thence to the locomotive boiler. It will be seenthat in traversing this line, water from tank 55 proceeds through thesteam ejector 86, a steam connection being made thereto from theaccumulator by opening the valve 88. Flash steam from the accumulator atabout 40 pounds pressure immediately mixes with the fresh feed water inthe inductor, en route to the locomotive boiler. This permits carrying apressure in the feed water line, and results in the introduction of thefresh refillv water at a temperature substantially above thepboilingpoint, say in the range of 220 to 250 degrees F., and at a pressureconsiderably above atmospheric. A corresponding heat con- :tent vof the.accumulator fluid, is thus delivered to the locomotive.

By thus filling the locomotive `boiler with Water ata temperature say ofthe order of 250 degrees F., instead of at the prevailing temperature,under the older practice, of 180 degrees F.., the steaming-up timeheretofore required, is consid- `erably reduced, as is the amountof fuelrequired `to raise the boiler to a steaming condition.

It will have been observed from vthe foregoing that a distinct saving iseffected in roundhouse practice, in that, without any extraneous sourceof heat, a locomotive boiler after cleaning and relling, possesses aheat content prior to resteaming represented by, say `3500 gallons `ofwater at a temperature. of 220 to 250 degrees fF.; undef' the olderpractice, due to undue waste and failure properly to reclaim the heatcontent of -blowoff Water, the same amount, say of 3500 gallons ofwater, existed prior to re-steaming, at a temperature of not to exceed180 degrees F.

It will also have been observed from the foregoing description that noextraneous source of heat need be employed to obtain the highertemperature of the incoming boiler feed water. The relatively largeramount of reclaimed heat is due in part to the confinement andmaintenance of the greater part of the original steam pressure, wherebythere is conserved a substantial part of the llatent Aheat ofvaporization. A major factor in heat .conservation consists in confiningthe flash steam within the sludge body with little loss, entirely withina closed system, at a pressure above atmospheric. The .heat savingincident to the .presentzmethod and apparatus, is also traceable inlarge measure to the use of the very em- :ient counterflow heatexchanging device 36. The necessary reduction of temperature Aof acertain amount of the water for purposes of washing, is accomplished inthe exchanger without any material `waste of heat; this heat beingutilized in, and imparted to the fresh water or boiler feed supply inthe tank A56. The use of .a steam and .water contact device, such as theheater head 58 of the .present example, also serves much moreefficiently than under prevailing practices, to transfer the heatcontentof the flash steam from tank .26, to the fresh water supply utilized forrell.

While the description has been particularized with respect to a methodand apparatus for reclaiming the 'heat of locomotive boiler fluids, theprinciples of the present invention -areapplicable equally, with orwithout minor changes, to stationary steam boilers, heating plantsutilizing steam, steam generators, and other analogous equipment. Thepresent detailed description of an illustrative embodiment of theinvention should not be understood in a limiting sense,rsince numerouschanges may be made in the parts, their combinations, and the practicesemployed in connection therewith, without departing from the fullintended scope of the invention as defined by the appended claims.

claim:

l. VThe herein described method of reclaiming heat from a steam boilerincident to blowoff and replacement of the boiler water supply, whichconsists in heating the supply water in three stages, namely, first bycirculation countercurrently to a flow of the blowoif water, secondly byadmixing a stream of fresh supply water, and a flow of flash steam fromthe blowoff water, and thereafter injecting steam, at a higher pressurethan said flash steam, into the supply water .and in introducing theheated supply water to the boiler.

2. The herein described method of reclaiming heat from a steam boiler,incident to replacement of the boiler Water supply, which consists inblowing off the boiler while under a relatively high pressure, into asteam-water container, and

`at a relatively low pressure in a second such container, in preheatingfresh water .by water from the `second container, and in .turbulentlyadmix- Aing streams .of preheated fresh supply Water and flash steamfrom the said second blowoff water container, out of contact with thebody of blowoff water therein, in injecting steam from the :highpressure container to the supply water, and

in adding the steam-treated supply water to the boiler for rellpurposes.

:3, The herein described method of reclaiming Yheat from a steam boileras an incident to boiler washing and replacement of the boiler watersupply, which consists in conducting .portions of the blowoff water intoseparate high and low pressure containers therefor, in cooling a portionof the blowoif water from the low pressure container by conduction ofits heat content to a stream of fresh boiler feed Water, in conducting.the cooled blowoff water to a reservoir therefor to effectprecipitation of a portion of the mineral content of the blowoff water,and thereafter utilizing the water from such reservoir for boilerwashing purposes, in utilizing the steam from the low pressure containerfor a second stage of heating of the feed water, and thereafterutilizing the steam from `the .high pressure container as a third stageof heating the feed water. v

4. The herein described method of reclaiming heat from a steam boiler,incident to washing the boiler and replacement of its water supply,which consists in conducting relatively high and -low temperatureportions of the boiler blowoff fluid to separate containers therefor, inutilizing a rela' tively low temperature portion of such blowoff uid forboiler washing purposes, in concurrently heating the feed water andcooling the wash fluid, by countercurrent circulation thereof throughadjacent heat transferring passages, in further heating the feed waterfrom the relatively low temperature fluid, and thereafter in a separatelstage, by contact with the high temperature fluid.

5. The herein described method of reclaiming heat from a steam boilerincident to replacement of the boiler water supply, which consists insegregating and separately confining quantities of the boiler blowoifwater and steam, as high and low temperature portions respectively, inutilizing the lower 4temperature portion of the blowoff fluid forheating, lby conduction, a supply of fresh feed water, in furtherheating the feed water by admixture thereof with flash steam from thesaid lower temperature portion of blowoff water and in still furtherheating the feed water by absorption -of the heat `content of the hightemperature portion incident to circulation for refill purposes.

6. The herein described method of reclaiming heat from a steam boiler asan incident to replacement of the boiler water supply, which consists instoring under pressure exteriorly of the boiler a substantial part ofthe boiler blowoff water, vstoring in a second container an additionalportion of the blowoff water, in concurrently circulating in separatesystems a stream of water from said second blowoff container and astream of fresh feed water, in subjecting said stream of fresh feedwater to a turbulent admixture with flash steam from said second blowoffcontainer,

and in thereafter subjecting the supply of fresh water to a flow ofsteam from the confined blowoff water, and introducing the supply ofsteamtreated fresh water to the boiler, under a substantial steampressure. v

7. In apparatus for reclaiming the heat of drained boiler iiuid, aboiler drain conduit, a tank structure for confining blowoff water andsteam under pressure, a connection between said tank structure and saidconduit, a fresh feed water conduit, means for preheating the fresh feedwater in said conduit, including elements for separately andcountercurrently circulating in adjacence thereto a portion of theblowoff water, a storage tank for the preheated feed water, an

.injector having a steam connection to said blowoff pressure tankstructure, a water inlet connection to said preheated feed water storagetank, and a discharge conduit for directing the steam treated feed waterfrom the injector to the boiler, for refill purposes.

8. Apparatus for reclaiming heat from drained boiler fluids, including alow pressure container and a high pressure container, each for blowofwater and steam, a conduit for fresh feed water, means for circulatingthe water from said low pressure blowoif container countercurrently andadjacently in heating relation to the flow of fresh feed water in saidconduit, means for effecting a further heating stage of the feed waterby contact with steam from the low pressure blowo container, a conduitarranged for directing the steam heated feed water, for boiler refillpurposes, and means in said conduit for utilizing the heat con- 1 tentof the high pressure container in a subsequent heating stage as the feedwater is utilized for refill purposes.

9. Apparatus for reclaiming heat from drained boiler fluids, including acontainer for receiving blowoif water and steam under pressure, a freshwater conduit for boiler refill purposes, a conduit for separately butadjacently circulating blowoif water countercurrently to the fresh waterfor preheating the freshboiler feed water while traversing its saidconduit, a storage tank for the preheated feed water, a heater ofsteam-water contact type connected for utilizing a portion of theblowoff steam for heating feed water prior to its introduction to thestorage tank, and a steam ejector having its steam supply connected tosaid blowoif container and being connected in the fresh water conduitbeyond the: storage tank, and adapted for the introduction of freshwater to the boiler, under substantial steam pressure.

l0. Apparatus for reclaiming heat from drained boiler fluid, including apressure container for receiving blowoff water and steam and conningsame in three fractions, at low, intermediate and high temperaturaaftertheir removal fromthe boiler, a fresh watersupply line, means connectedinto the blowoff container and fresh water line for adjacentlycirculating separate streams of water therefrom for heating the freshwater supply, by utilization of the low temperature fraction, means forfurther heating the fresh water supply in a second stage by contact withthe intermediate fraction of fiuid from said blowoff container, meansforconducting the freshwater from the last said heating means to theboilenlfor refill purposes and a heat transfer device associated withthe said conducting means, said device utilizing the said hightemperature fraction as aivnal heating stage incident to rell. l1.Apparatus for reclaiming heat from boiler blowoif uids, includingavblowoffpressure container, a pressure tank forming a reservoir forVblowoff water, the container and reservoir being provided with steamspaces, valved conduits from the boiler to said Vcontainer andreservoir, a fresh water supply conduit, a heat exchanger havingseparate circulatory systems connected respectively to said blowoifreservoir and to said supply conduit, a water heater of steam-watercontact type, having a steam connection to the steam space of saidblowoff reservoir and a water connection from said heat exchanger,afresh water storage tank communicating with the contact type heater,andv connections for supplying the storage tank therefrom, a steamejector connected to the steam space of said blowoff pressure container,a conduit from the fresh water storage tank to said ejector, a pump inthe last said conduit, and a conduit from said ejector to the bollen-forrefill purposes.

l2. Apparatus for reclaiming heat from boiler blowol uids, including ablowoff header, adapted to be connected to the boiler to be drained, awash out header adapted to be connected to the boiler for washingpurposes, a feed water header adapted for the supply of fresh water to aboiler after draining and cleaning thereof, a pipe line from saidblcwoff header, provided with two branches, valves in said branches, apressure accumulator for blowoff water and steam, adapted to contain asubstantial portion of the blowoff water from the boiler undertreatment, said accumulator being connected to one of the branches ofsaid blowoff pipe, a storage tank for the remaining blowoif water,connected to the other of said branches, the pressure accumulator andstorage tank each being closed and having a steam space in its upperportion, a heat exchanger of countercurrent type, characterized by anouter circuit and an innerrcircuit, the outer circuit of the exchangerbeing connected to the water-containing part of said blowoff waterstorage tank, a fresh water supply conduit connected to the innercircuit ofthe exchanger, a water heater of steam-water contact typey awater connection to said heat-er from the inner circuit of said heatexchanger, a steam connection to said heater from the steam space of theblowoif water storagetank, a fresh water storage tank and a fresh waterconnection therefrom to said heater, means including a pump connectingthe freshwater storage tank to the feed water header, a settlingreservoir for blowoif water, having a supply connection to the outercircuit of saidl heat exchanger,`means including a pump for deliveringwater under pressure from said settling reservoir into-the washoutheader, for boiler washing purposes, and a steam ejector, having a steamconnection with the steam space of the blowoif pressure accumulator andconnected with the fresh water storage tank through the -pump andassociatedmeans first'aforesaid, the ejector being further provided withan outlet connectionto the first said feed water header.

f MINOR W. STOUT. l

